Task groups

[synhershko]

Currently, all IUpdateTask objects are applied in one go, or rollbacked at once if something goes wrong. NAppUpdate should support grouping of tasks, so a feed (NauXml or any other) can specify what tasks are related to each other. This way, even if one task fails another unrelated one can still be completed.

Presenting a new "BatchTask" object will probably do the job, but some thought needs to be put into this, so functionality such as update descriptions, reporting, rolling back etc will all be compatible and done correctly.

[jamielennox]

have a look at my branch taskgroups for my ideas.

If you keep a group simply as a task that performs other tasks then the flow of the library changes very little. That branch also works without breaking the NAppXML format.

It is a little unclean and not ready to be brought across but it should show my thoughts